Adds main landmark in new app shell
Adds main landmark in new app shell

eessex/force,oxaudo/force,eessex/force,joeyAghion/force,oxaudo/force,artsy/force,joeyAghion/force,artsy/force-public,artsy/force-public,artsy/force,oxaudo/force,artsy/force,oxaudo/force,eessex/force,joeyAghion/force,joeyAghion/force,eessex/force,artsy/force